System of control



R. E. HELLMUND.

SYSTEM OF CONTROL.

I APPLICATION FILED JUNE 18, 1919. I

I 1,416,024. Patented May 16, 1922'.

2 SHEETS-*SHEET I.

INVENTOR AM ATT ORNEY WITNESSES: J

R. E. HELLMUND.

SYSTEM OF CONTROL.

APPLICATION FILED JUNE 18. 1919.

1,416,024. t d May16,1922.

2 SHEETS-SHEET 2.

L.. I .5 d & 7 J6 mun v l v 7f 7/ i167 WITNESSES: INVENTOR /5W lFuao/FE. Hcl/mund BY ATTdRNEY is a specification.

UNITED". STATES PATENT orricg. v

aunomr n Emmmuim, or SWISSVALE, rmm'sinvnnm, nssmnon r0 wns'rx'ne noose mncmo a unnurac'ruamc COMPANY. A som o VANLL sysrmm or common Specification 01mm" mum. P t t d' '1 1 3,

Application n; is, 1919. [semi no. scams.

To all whom it may concern."

Be it known that I, Ruoonr E. Hami- MUND, a citizen of the German Empire, and a resident of Swissvale, in the county of of Pennsylvania, have invented a new and useful Improvement in Systems of Control, of which the following My invention relates to systems of control and control apparatus for use in connection a with electric-railway-motor systems of the I well-known automatic type, and it has special relationto pilot motor-operatedcontrol- 'lers, and the like.

J imy or the equ valent, that is operated by. means soription,

i companymg .ent invention,

'trol of the system Inautomatic control systems, as provided by the prior art, one handicap has resided in the use of a current relay, or the equivalent, having only one or two settings or critical operating values, whereby, at times of light load; too rapid acceleration has been obtained, while at times of heavy load, undesirably slow or totally interrupcdaccelerating operation has resulted.

One object of the present invention is to provide a system of the above-indicated character which shall eliminate the handicap in question by efiec'ting automatic con-y through a governing device having a time-element that is inherently dependent uponthe load of the system. In

this way, underv light-load conditions, the

accelerating operation is expedited 'to' the proper degree, while, under heavy-loadxo'onditions. a slower rate of acceleration 1s inherently provided. i

More specifically stated, a isthe object of invention to provide a master controller, of a pilot-motor having a field winding energized in accordance with the load of the main motor to be controlled. i Other objects of the invention, relating to the simplicity and'reliability' ofconstruction and to the novel mode of operation of my pilot-motonoperated controller, will becompound structure, comprising a bar or rod come evident from the'following detailed detaken in conjunction with the acview, partially in elevation, of a master controller constructed and organized Fig. 2 and Fig.3 are etail views of parts of the controller shown in Fig. -1', and Fig. 4 is a simplified diagrammatic view 0 a control system embodying a electric motor, for example. 12 is also provided with a pair of auxiliary by the switch arm ,mounte'd .upon .a sleeve 17 which .naledw'ithin a bearing end of the shaft extending drawings, wherein Fig. 1 is a section and pantiallyinj 26 is integrally in accordance with the respilot motor connected in circuit in accordtuating a. switch member or arm-7 that cooperates with a drum-actuating device 8 that 15 primarily governed by a pilot motor 9.

The contro drum 4 and its attendant apparatus may be of any familiar type, comprising a suitable finger-base 12 upon which aremeunted apluralityof control fingers 13 for engaging or bearing upon one or more contact segments, which do not appear on the drawing, for the familiar purposeof governing the automatic-control o ration, of an l he 'finger base control fingers 14 that are adapted 'to en gage a pair of contact segments or rings 15 (shown dotted because located on the remote side of the which, under op-- crating conditions, are also engaged by abifurcated contact seg'L ;nt 16 that inafter setforth-Y y The control drum 4 isnotdirectly actuis actuated i 7, in a mannerto behere. 8

ated by the operating shaft-5-but is rigidly longitudinally extending set-screw 20, for example, of the operating. shaft or bracketmember 21, the upper through the top cover member 2 for the pun spec of attachment to the operating han- The control arm 71may be of integral -or loosely encloses the shaft. The lower end 18. of the sleeve rests hub-19 for the switch arm "7, the hub. rigidly attached to the shaft 5,- by means oi a The lower end 5' is suitably 'jouring 22 that extends substantiallyhorizontally from the hub 19'and terminates in a verti-. cally extending portion 25. A cam'member or otherwise secured to one side of the bar the upper end of an ad insulatin block 29, for t e purpose of carrying the ifurcated contact segment 16,, as clearly shown in Fig. 1. I

aoent, face with an 25, which is provided near The drum-actuating device 8 comprises a horizontal engaging member or circular plate 35 having a plurality of upstanding teeth or lugs 36 separated by notches or recesses 37. The plate is rigidly secured by means of bolts 38, or otherwise, to a gearwheel 39 which, like the plate 35, is loosely mounted upon the sleeve 17. The pinion 40, which is rigidly mounted upon the operating shaft 41 of the pilot motor 9, meshes with the gea-r-wh'eel 39, whereby the control drum 4 may be rotatively actuated in a manner to be set forth. I

The apparatus 8 further comprises a locking bar 42 which is pivotally mounted at 43 upon a depending lug 44 of the control drum. A fiat spring 46 may be secured to one side of the locking bar 42 for a purpose to be hereinafter described.

Near the lower end of the operating shaft 5, a familiar position-accentuating device is provided, comprising a star-wheel 50 having notches corresponding to the. positions of the control drum (although the star-wheel is movable relative to the drum), and a pawl '51 having an intermediate pivotal mounting for the purpose of engaging the notches of the star-wheel, towards which the pawl is biased through the agency ,of a coil spring 52, the outer end of which is secured by a screw 53 to any suitable portion troller frame.

A. similar position-accentuating device is likewise provided upon the upper surface of the control drum 4, comprising a star-wheel 55 that is rigidly secured to the drum 4 and a co-operating spring-biased pawl 56. i

The circuit connections of Fig. 4 will now be described in order to render the complete mechanical and electrical operation of the master controller clear. The illustrated system has been simplified to set forth only the essential elements, since automatic control systems, for railway motors, for example, are so familiar in the art that a complete illustration and detailed explanation thereof in connection with the present invention is believed to be unnecessary. In addition to the control fingers 14 and 16 and the contact segments 15, which have been illustrated on an enlarged scale for the sake of clearness the system comprises suitable supply-circuit conductors Trolley and Ground; a main dynamo-electric machine, such as a car-propelling motor, having a commutator-type armature Al and .a series-connected field winding F 1; a line switch 61; a control resistor 60; a manually-operated emergency switch 62; and the pilot motor 9, which c0Inprises a commutator-type armature 65 and a plurality of field COIlS 66 and 67.

When the line switch 61 has been closed, in the usual manner, through the actuation of the control drum 4, a main circuit is established from the Trolley through the line of the conswitch, armature A1 and field winding F1 to Ground. An auxiliarycircuit servesto connect the control resistor 60 across the supply-circuit conductors, this control resistor being employed for familiar purposes, such as supplying suitably low-voltage energy to the actuating coils of the various controlling switches that are employed in automatic control systems, as will be understood.

One such low-voltage circuit is continued from a suitable point in the control resistor 60 through conductor 70, control fingers 14 and 16, all of which engage contact segments 15 under operating conditions, whence circuit is completed through pilot-motor armature 65, field coil 66 and conductor 71 to Ground. It will be notedthat the circuit just traced is completed whenever control finger 16 bridges contact segments 15, irrespective of the open or closed condition of the line switch 61. Althoughthe other field coil 67 is initially connected in a live circuit, the energization of the coil is so weak as to be substantially negligible.

Whenever the line switch is closed to effect energization of the main field winding F 1, however, the field coil 67 for the pilot motor is also fully excited by reason of the connection thereof through conductors 71 and 72, across the terminals of the main field winding F 1. In this way, the excitation of the pilot motor is rendered inherently dependent upon the load of the main motor, since the field winding F1, in so far as the pilot-motor field-coil 67 is concerned, acts as a resistor, the voltage across which varies in accordance with the load of the main motor.

Consequently, the speed of the pilot motor 9, and, therefore, the movement of the control drum 4, by means of the mechanical con nection to be described, is inherently de pendent upon the main-machine load, being slow or fast under heavy-load and light-load conditions, respectively. This is a very desirable feature, since rapid automatic"-operation of the controlling switches is desirable under light-load conditions,while slow automatic control is required when the motors are heavily loaded, to prevent over-load conditions therein.

Referring to Fig. 1, the operation of the structure there shown may be set forth as follows: The operating handle 6 may be quickly moved (in a clockwise direction as viewed from above) to any desired position, corresponding to half or full speed, for example, of one or more motors, and the operating shaft 5, together with the switch arm 7, will be held in the selected position by means of the position-accentuating device comprising the star-wheel 50 and the pawl uch movement of the switch arm 7 immediately effects the desired engagement of the control finger 16 and the contact segthe engaging pl drum is desired, the spring 46 up Furthermore, the concurrent removal of the cam member 26 permits the locking bar 42-to drop into one of the notches 37 of ate 35. Consequently, the rotative movement of the plate 35, which is effected through the agency of the pinion 40 and gear-wheel 39, as soon as the pilot motor 9 is energized, produces corresponding rotative movement of the control drum 4 as soon as th'e'lo'cking bar engaging plate 35. Thus, the ation of the control drum 4 to its various positions is directly governed by the pilot motor 9, the time-element of operation of which is inherently dependent upon the load of the main machine, as previously described, whenever the line switch 61 has been closed in the usual manner by movement of the control drum 4.

The. drum 4 is thus rotated from its off position, in the same direction as'the arm 7 was previously moved, until the position thereof corresponds to the selected position of the intially-moved switch arm 7 whereupon the locking bar 42 rides along the cam member 26 into the disengaged position with respect to the engaging plate 35 that is shown in the figures. The mechanical connection between the pilot motor 9 and the drum 4 is thus interrupted and, at substantially the same time, the control finger 16, having travelled backwardly over the contact segments 15, becomes disengaged therefrom to open the circuit of the pilot motor. The co-operating parts of the device are so proportioned that the occupation of the desired position by the drum 4 and the stopspeed of oper- .page of the pilot motor are practically si'multaneous. a

The control drum 4 will thus automatically follow the initial manual movement of the operating handle 6 to any selected posi tion, the speed of the drum and, therefore, the rate of acceleration of the main motors, being, meanwhile, dependent uponthe load thereof.

When it is desired to cut off the power, the handle 6 may be rapidly returned to the off position the switch arm 7 maintaining the locking bar 42 in the illustrated upper osition, whereby such return movement is effected independently of the operation of the engaging disc 35 and the pilot motor 9, which may remain in the positions they happen to occupy and still bein readiness for the next control operation.

If step-by-step movement of the control on the locking bar 42 comes into play in the following manner: Upon movement of the operat- 42 iscaught by the 'ation of the control connected. Under such conditions,

and the switch arm 7 to the first position, the locking bar 42 becomes disengaged from the cam-member 26 and drops into one of the notches 37 in the en aging disc 35, which, as before, is driven y the pilot motor 9. At first, the corresponding lug 36 compresses the spring 46 until the resultant pressure is suflicient to overcome the biasing action of the pawl 56 upon the star-wheel 55. As soon as such critical presing handle 6 sure is reached, the drum 4 rapidly moves to the next operating position as the compressed spring 46 r'eturns'to its normal position. Thus, the desired step-by-step movement may be efl'ected, the illustrated apparatus providing a rapid actuation corresponding to each controller notch, independently of the rate of movement of the operatin handle 6.

If des red, the brief time necessary for starting the pilot motor, upon each successive movement of the control drum 4 in a forward direction, may be saved by permitting the pilot motor to run continuously. In this event, the control fingers 14 and 16 and the contact segments 15 may, of course, be dispensed with, and direct connection of the pilot-motor armature 65 may then be madethrough the agency of switch 62, for example, to the control resistor 60.

If, for any reason, straight manual operdrum 4 by the operating handle 6 is desired, it is sary to insert a screw or pin in the opening 75 (shown in Fig. 2), whereby the locking bar 42 and the cam member 26 are rigidly;

it wil be evident that the forward and reverse merely necesmovement of the control drum is directly dependent upon ating handle 6.

It will be seen that I have thus provided a pilot-motor-operated controller or switching device, the speed of movement of which and, therefore, the rate of acceleration of the motor to be governed, is inherently dependent upon the load ofthat motor. Furthermore, my complete control may readily be substituted in any of the present automatic control s stems for the master controller now emp oyed, by the addition of the illustrated wires 70,. 71 and 72 for the pilot motor, the remainder of the system being connected as before. It will be appreciated that any desired degree of dependency of the rate of acceleration upon load may be provided by suitable adjustment or simple re-organizzation of the pilotmotor-excitation circuits.

I do not wish to be restricted to the specific structural details, circuit connections or arrangement of parts herein set forth as various modifications thereof may be effected without departing from the spirit and scope of my invention. I desire, therefore,

the'movement of the operthe ma'nr motor' that only such limitations shall be imposed as are indicated in the appended claims.

I claim as my invention:

1. In control apparatus, the combination with. a rotatable multi-position switching device, of a switch member rotatably associated therewith power-operated means, means for detachably connecting said power-operated means to said switching device, and means for rendering means ineffective when and the switch member occupy predetermined relative positions. a

2. In control apparatus, the combination with a rotatable multidevice, of a switch mem ciated therewith, dynamo-electric means, means dependent u for connecting sai' dynamo-electric means to said switchm device, and means for deenergizin said ynamo-electric means when the -switc ing device and the switch member occuply predetermined relative positions.

control apparatus, the combination with a rotatable contact-carrying drum, of a relatively movable contact-carrying arm bearin upon' said drum, apilot motor governedy said arm for actuating said drum,

and means adapted to break the pilot-motor circuit .upon engagement of said arm and a portion of said drum.

4. In control apparatus, thecombination with a rotatable contact-carrying drum, of a relatively movable contact-carrying arm bearing upon said drum, means for manually operating said arm to selected positions, a movable engagin ber normally free rom said engaging member and movable with said drum, and a pilot motor governed by said arm for actuating said engaging member to engage said locking member under certain conditions, whereby the drum is moved into a position corresponding to the position of said arm.

5. In control apparatus, the combination with a rotatable contact-carrying drum, of

said power-operated the switching device.

osition switching er rotatably asso- 11 said switch member.

biasing action of member, a locking mema relatively movable contact-carr ing arm bearing upon said drum, -means or manually o crating said arm to selected ositions, a note ed engaging member, a locking member movable with said drumand initially held free from said engaging member by said arm, a pilot motor electrically gov erned by said arm for actuatin said engaging member to' catch said loc ing member after movement of said arm, whereby the drum is moved into a position corresponding to the position of said arm, and means for interrupting the pilot-motor circuit upon the coincidence of such positions.

6. In control apparatus, the combination with a rotatable contact-carrying drum,.of a relatively movable contact-carr ing arm bearing upon said drum, means or manually operating said arm in astep-by-step manner, a notched engaging member, a lockin member movable with said drum and initially held free from said engaging member by said arm, a spring secured to said lockin member, a biased position-accentuatin evice associated with said drum, and :1 pi ot motor electrically governed by said arm' for actuating said engaging member to each movement of said arm, whereby the said position-accentuating device is intermittently overcome to effect relatively rapid movements of said drum to successive positions.

7. In control apparatus, the combination with a rotatable contact-carrying drum, of a relatively movable contact-carrying arm bearing upon said drum, a pilot motor, manual meansfor' actuating said arm and for effecting enga ement of said motor and said drum, am? means adapted to break the pilot-motor circuit upon engagement of said arm and aportion of said drum. y

In testimony whereof, I have hereunto subscribed my name this 6th day of June, 1919.

RUDOLF E. HELLMUN D.

receive said locking member and spring after 

